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safasmets
safasmets asked in Science & MathematicsMathematics · 1 decade ago

can someone help me understand some imaginary number problems?

(-2-5i) - (7-2i)

(2+4i)^2

Ahhhh help

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  • ?
    1 decade ago
    Favorite Answer

    I think u know that i = sqrt(-1)

    so, if there are i terms in an equation add pr subtract them seperately.

    so

    -2 - 5i - 7 +2i = -3i - 9

    and for 2nd one use (a + b)^2 = a^2 + b^2 +2ab

    so that gives

    4+ 16i^2 + 2(2)(4i) = 4 - 16 + 16i ( i multiplied by i is -1)

    so that gives

    -12 + 16i

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